At the hairiest junctures of a Washington Nationals game, pitching coach Steve McCatty emerges from the dugout and trudges to the mound. When a pitcher is struggling, McCatty is the man called upon to help make it stop. He initiates one of the most public — and perhaps even embarassing — coaching moments in professional sports: the mound visit. It is perhaps his least favorite part of the job.

“It’s never fun,” McCatty said. “Guys don’t want to come out of the game. They don’t want you coming out there. Guys don’t like to have their rhythm broken up. I tell them all the time, ‘I’m not coming out there because I feel like coming out there.’ I ain’t going out there to say, ‘Nice job. Good pitch.’ ”

In that moment, which also involves the catcher in a conference on the mound, McCatty plays part psychologist and part pitching coach — but mostly psychologist. McCatty, of dry and sarcastic humor off the field, approaches the visits with utter seriousness. His foremost mission is to calm the pitcher and give a brief pep talk.

“Most of the time, when things start to go bad, you start to get in panic mode, and that’s the one thing you don’t want,” said McCatty, 59, a former starter for the Oakland Athletics. “I try to keep them from doing that.”

Each pitcher, however, handles difficult situations differently. McCatty, known mostly by his nickname, “Cat,” uses the same line with each of them: “You’re one pitch away. Just relax. Breathe. Make one good pitch here and you’re out of the inning.”

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Beyond that, McCatty rarely mentions mechanics. When needed, he reminds pitchers how to attack a hitter in that situation. Most are quiet and listen to McCatty’s spiel, from Stephen Strasburg to Jordan Zimmermann to Tyler Clippard. (“I don’t mind it at all,” Zimmermann said.) The Latino players speak enough English for McCatty to convey the same message.

“Cat is really good at the mental side of pitching, and he understands how to get through innings and how to get to through games,” reliever Craig Stammen said. “I would say every time he comes out to the mound it’s pretty much the exact same thing.”

Except for when it comes to two pitchers: reliever Drew Storen and starter Gio Gonzalez. Gonzalez, a jovial character, chides McCatty and pushes his buttons off the mound. So when McCatty visits the mound, there’s often joking banter. “It’s like talking to your best friend whenever you get a chance,” Gonzalez said.

Storen simply dislikes mound visits. When he is struggling, he wants to be left alone to solve the situation. Storen, friendly off the field but emotional on it, doesn’t respond to positive reinforcement in tough situations. McCatty tells him that he will be fine, and Storen chirps back. Even though he doesn’t like it, Storen knows the main purpose of the visit is to remind him to relax and simplify the situation, which is easily forgotten as things spiral downward.

“I’m usually not too happy, and at the time I don’t feel like I have to hear what he has to say, even though I do,” Storen said. “Him and I have done it so much it’s to the point where he knows what he’s going to get. It’s not going to be a nice, easygoing conversation.”

During a mound visit, Gonzalez even jokingly told McCatty to go back to the dugout, followed by a threat of bodily harm.

“He’ll get mad and say stuff, and I’ll yell back at him,” McCatty said. Catcher Kurt “Suzuki will just laugh.”

“It’s funny when he goes out to meet with Gio,” Suzuki added. “That’s the best. I can’t repeat anything. It’s not bad. It’s just not family-friendly.”

The timing of the mound visit is decided by McCatty or Manager Davey Johnson, whose visits almost always signify a change in pitchers. With some exceptions, Major League Baseball rules allow only one visit by a coach or manager per inning without changing pitchers. There are no rules on the length of a mound visit, according to a league spokesman, but umpires are instructed to break up visits based on the game situation. For example, if a coach is purposely walking slowly to give another pitcher additional time to warm up, an umpire will put an end to the conference sooner.

That is when strategy is involved. Reliever Ryan Mattheus said he saw pitching coaches in the minors use the conference as a chance to voice disgust over the strike zone to the umpire when he came to the mound to break up the visit. But those tricks make for frank small talk on the mound when the pitcher realizes the ploy.

‘You know why I’m out here,’” Stammen said he has heard before. “ ‘We just gotta get another guy loose. But you can get out of this inning.’ It’s part of the game. When you’re getting hit, it ain’t fun being out there.”

Across the sport there are infamous stories about managers or pitching coaches using humor to lighten the mood during the visits. In Game 1 of the 1995 American League Championship Series, Mariners Manager Lou Piniella walked to the mound in the first inning with the bases loaded and no outs and talked to struggling young pitcher Bob Wolcott not about pitching but hunting in Oregon. Coaches might even ask pitchers what they ate for breakfast or what was planned for dinner — anything to get the player’s mind off the stressful situation.

Mattheus had that happen to him in 2005 when he was with Asheville, the Class A affiliate of the Colorado Rockies, and coughing up hits. Pitching coach Greg Booker, who now holds the same position with a Nationals affiliate, Class AAA Syracuse, came to the mound, kicked dirt into holes and retreated to the dugout. Mattheus notched the final out of the inning and questioned Booker in the dugout.

“He said, ‘I wanted you to stop thinking so much about what you were doing out there, and I wanted you to think about why I came out there and didn’t say anything,’ ” Mattheus said. “And it kind of worked.”

McCatty prefers to keep the focus on making the pitcher relax. He believes anything more than a brief mention of mechanics — rushed or out-of-line delivery, for example — clouds the pitcher’s mind. By reiterating to the pitcher that his stuff is good enough, McCatty wants them to believe in their strengths.

“I’ve had guys where we’ve had a lead and he gave up a home run, and I said something like, ‘I didn’t think that ball was out when he hit it,’ ” McCatty said. “And then loosen him up. But most of the time, it’s not to joke but to relax.”